Coexistence of persistent left superior vena cava with common inferior pulmonary vein in a patient with atrial fibrillation

Coexistence of a persistent left superior vena cava (PLSVC) with a common inferior pulmonary vein (CIPV) is very rare. The electrical assessment of those thoracic veins was performed during the atrial fibrillation ablation

The effectiveness of cardiac resynchronization therapy for patients with New York Heart Association class IV non-ambulatory heart failure

Background: We reviewed the effectiveness and safety of cardiac resynchronization therapy (CRT) for patients with New York Heart Association (NYHA) class IV non-ambulatory heart failure (NAHF). Methods: From 2006 to 2011, 310 patients underwent CRT at Kobe University Hospital and Himeji Cardiovascular Center because of heart failure. Of these, 29 NAHF patients were retrospectively analyzed. The control group comprised 21 age- and ejection fraction-matched patients with NAHF who did not undergo CRT from the ICU database of Kobe University Hospital. The primary endpoint was all-cause death and hospitalization for heart failure. Response was defined as a >15% reduction in left ventricular end-systolic volume (LVESV). Results: CRT was performed successfully without serious complications in all patients. Twenty-three patients (79%) were discharged 19±15 days after CRT implantation, while 6 (21%) died during their hospital stay due to progressive heart failure. Compared with the control group, patients in the CRT group showed significant improvements in the primary endpoint (log-rank p=0.04). Six patients (21%) were defined as responders and the Kaplan–Meier curve showed that responders experienced a better outcome than non-responders (log-rank p=0.029). LV dyssynchrony before implantation was significantly related to the occurrence of the primary endpoint (p=0.02). Conclusions: CRT can be safely used in patients with NAHF and can improve long-term patient outcomes, especially in treatment responders

The Rho/Rho-kinase Systems Are Involved in Rapid Pacing-induced Changes of Atrial Refractory Period in a Canine Model

Introduction: The Rho/Rho-kinase pathway has been related to various physiological responses of the cardiovascular system. Previous reports have suggested a significant effect of Rho signals on the electrophysiological characteristics of the heart. We hypothesized that the Rho/Rho-kinase system would contribute to the rapid pacing-related change of atrial effective refractory period (AERP). Methods and Results: In 17 dogs, AERP was measured at the right atrial appendage (RAA) and posterior left atrium (LA) before, during, and after 6-hours rapid atrial pacing at 500 bpm. Saline control (n = 5), verapamil (n = 5), or fasudil (n = 7) were infused throughout the protocol. The shortening of AERP after rapid pacing was abrogated by the administration of verapamil, as reported in previous studies. Furthermore, fasudil (Rho/Rho-kinase inhibitor) influenced the change of AERP in a manner similar to the infusion of verapamil throughout the experiments. Conclusions: Since the AERP was attenuated by fasudil, rapid pacing-related atrial electrophysiological changes might involve the Rho/Rho-kinase pathway

Acquisition of the pulmonary venous and left atrial anatomy with non-contrast-enhanced MRI for catheter ablation of atrial fibrillation: Usefulness of two-dimensional balanced steady-state free precession

Background: Usually, the pulmonary venous and left atrial (PV–LA) anatomy is assessed with contrast-enhanced computed tomographic imaging for catheter ablation of atrial fibrillation (AF). A non-contrast-enhanced magnetic resonance (MR) imaging method has not been established. Three-dimensional balanced steady-state free precession (3D b-SSFP) sequences cannot visualize the PV–LA anatomy simultaneously because of the signal intensity defect of pulmonary veins. We compared two-dimensional (2D) b-SSFP sequences with 3D b-SSFP sequences in depicting the PV–LA anatomy with non-contrast-enhanced MR imaging for AF ablation. Methods: Eleven healthy volunteers underwent non-contrast-enhanced MR imaging with 3D b-SSFP and 2D b-SSFP sequences. The MR images were reconstructed on the 3D PV–LA surface image. Two experienced radiological technicians independently scored the multiplanar reformatted (MPR) images on a scale of 1–4 (from 1, not visualized, to 4, excellent definition). The overall score was a sum of 5 segments (LA and 4 PVs). Results: In the 2D b-SSFP method, MR imaging was successfully performed, and the 3D PV–LA surface image was precisely reconstructed in all healthy volunteers. The image score was significantly higher in the 2D b-SSFP method compared to the 3D b-SSFP method (19 [19; 20] vs. 12 [11; 15], p=0.004, for both observers). No PV signal intensity defects occurred in the 2D b-SSFP method. Conclusions: The 2D b-SSFP sequence was more useful than the 3D b-SSFP sequence in adequately depicting the PV–LA anatomy

Prophylactic catheter ablation of ventricular tachycardia before cardioverter-defibrillator implantation in patients with non-ischemic cardiomyopathy: Clinical outcomes after a single endocardial ablation

Background: Outcomes related to prophylactic catheter ablation (PCA) for ventricular tachycardia (VT) before implantable cardioverter-defibrillator (ICD) implantation in non-ischemic cardiomyopathy (NICM) are not well characterized. We assessed the efficacy of single endocardial PCA in NICM patients. Methods: We retrospectively analyzed 101 consecutive NICM patients with sustained VT. We compared clinical outcomes of patients who underwent PCA (ABL group) with those who did not (No ABL group). Successful PCA was defined as no inducible clinical VT. We also compared the clinical outcomes of patients with successful PCA (PCA success group) with those of the No ABL group. Endpoints were appropriate ICD therapy (shock and anti-tachycardia pacing) and the occurrence of electrical storm (ES). Results: PCA was performed in 42 patients, and it succeeded in 20. The time to ES occurrence was significantly longer in the ABL group than in the No ABL group (p=0.04). The time to first appropriate ICD therapy and ES occurrence were significantly longer in the PCA success group than in the No ABL group (p=0.02 and p<0.01, respectively). Conclusion: Single endocardial PCA can decrease ES occurrence in NICM patients. However, high rates of VT recurrence and low success rates are issues to be resolved; therefore, the efficacy of single endocardial PCA is currently limited

Incidence of esophageal injury after pulmonary vein isolation in patients with a low body mass index and esophageal temperature monitoring at a 39 °C setting

Background: Esophageal injury following catheter ablation of atrial fibrillation (AF) is reported to occur in 35% of patients. Even with a low energy setting (20–25 W), lesions develop in 10% of patients. Body mass index (BMI) has been reported to be a predictor of esophageal injury, indicating that patients with a low BMI (<24.9 kg/m2) are at a higher risk. We hypothesized that catheter ablation with a lower energy setting of 20 W controlled by esophageal temperature monitoring (ETM) at 39 °C could prevent esophageal injury even in patients with a BMI <24.9 kg/m2. Methods: Twenty patients with AF were included (age, 63±8 years; BMI, 22.9±1.3 kg/m2, left atrium diameter, 44±11 mm). If the esophageal temperature probe registered a temperature of >39 °C, radiofrequency (RF) application was stopped immediately. RF application could be performed in a “point by point” manner for a maximum of 20 s. Endoscopy was performed 1–5 days after ablation. Results: Esophageal mucosal injury was not observed in any patient in the study. Conclusions: Catheter ablation using ETM reduced the incidence of esophageal injuries, even in patients with a low BMI

Visualizing radiofrequency lesions using delayed-enhancement magnetic resonance imaging in patients with atrial fibrillation: A modification of the method used by the University of Utah group

Background: Atrial tissue fibrosis has previously been identified using delayed-enhancement MRI (DE-MRI) in patients with atrial fibrillation (AF). Although the clinical importance of DE-MRI is well recognized, the visualization of atrial fibrosis and radiofrequency (RF) lesions has still not been achieved in Japan, primarily because of the differences in contrast agents, volume-rendering tools, and technical experience. The objective of this study was to visualize RF lesions by using commercially available tools. Methods: DE-MRI was performed in 15 patients who had undergone AF ablation (age, 59±4 years, left atrium diameter, 40±2 mm). Specific parameters for MR scanning obtained from previous reports were modified. Results: Of the 15 images, the images of three patients were uninterpretable owing to low image quality. RF lesions could be visualized in 8 (67%) of the 12 patients. Conclusions: In the current study, we successfully demonstrated that RF lesions could be visualized in Japanese patients using DE-MRI, although only commercially available tools were used